diff --git a/vlib/math/fractions/fraction.v b/vlib/math/fractions/fraction.v
index ac8a41853a..cc52cdc13c 100644
--- a/vlib/math/fractions/fraction.v
+++ b/vlib/math/fractions/fraction.v
@@ -79,6 +79,7 @@ pub fn (f1 Fraction) divide(f2 Fraction) Fraction {
 
 // Fraction reciprocal method
 pub fn (f1 Fraction) reciprocal() Fraction {
+	if f1.n == 0 { panic('Denominator cannot be zero') }
 	return Fraction{f1.d, f1.n}
 }